The case of a new numa node got missed in avoiding using the node info from page_struct during hotplug. In this path we have a call to register_mem_sect_under_node (which allows us to specify it is hotplug so don't change the node), via link_mem_sections which unfortunately does not. Fix is to pass check_nid through link_mem_sections as well and disable it in the new numa node path. Note the bug only 'sometimes' manifests depending on what happens to be in the struct page structures - there are lots of them and it only needs to match one of them. Fixes: fc44f7f9231a ("mm/memory_hotplug: don't read nid from struct page during hotplug") Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> --- drivers/base/node.c | 5 +++-- include/linux/node.h | 8 +++++--- mm/memory_hotplug.c | 2 +- 3 files changed, 9 insertions(+), 6 deletions(-) diff --git a/drivers/base/node.c b/drivers/base/node.c index 7a3a580821e0..a5e821d09656 100644 --- a/drivers/base/node.c +++ b/drivers/base/node.c @@ -490,7 +490,8 @@ int unregister_mem_sect_under_nodes(struct memory_block *mem_blk, return 0; } -int link_mem_sections(int nid, unsigned long start_pfn, unsigned long nr_pages) +int link_mem_sections(int nid, unsigned long start_pfn, unsigned long nr_pages, + bool check_nid) { unsigned long end_pfn = start_pfn + nr_pages; unsigned long pfn; @@ -514,7 +515,7 @@ int link_mem_sections(int nid, unsigned long start_pfn, unsigned long nr_pages) mem_blk = find_memory_block_hinted(mem_sect, mem_blk); - ret = register_mem_sect_under_node(mem_blk, nid, true); + ret = register_mem_sect_under_node(mem_blk, nid, check_nid); if (!err) err = ret; diff --git a/include/linux/node.h b/include/linux/node.h index 41f171861dcc..6d336e38d155 100644 --- a/include/linux/node.h +++ b/include/linux/node.h @@ -32,9 +32,11 @@ extern struct node *node_devices[]; typedef void (*node_registration_func_t)(struct node *); #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_NUMA) -extern int link_mem_sections(int nid, unsigned long start_pfn, unsigned long nr_pages); +extern int link_mem_sections(int nid, unsigned long start_pfn, + unsigned long nr_pages, bool check_nid); #else -static inline int link_mem_sections(int nid, unsigned long start_pfn, unsigned long nr_pages) +static inline int link_mem_sections(int nid, unsigned long start_pfn, + unsigned long nr_pages, bool check_nid) { return 0; } @@ -57,7 +59,7 @@ static inline int register_one_node(int nid) if (error) return error; /* link memory sections under this node */ - error = link_mem_sections(nid, pgdat->node_start_pfn, pgdat->node_spanned_pages); + error = link_mem_sections(nid, pgdat->node_start_pfn, pgdat->node_spanned_pages, true); } return error; diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index f74826cdceea..25982467800b 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1158,7 +1158,7 @@ int __ref add_memory_resource(int nid, struct resource *res, bool online) * nodes have to go through register_node. * TODO clean up this mess. */ - ret = link_mem_sections(nid, start_pfn, nr_pages); + ret = link_mem_sections(nid, start_pfn, nr_pages, false); register_fail: /* * If sysfs file of new node can't create, cpu on the node -- 2.16.2